1 /* 2 * Block driver for Hyper-V VHDX Images 3 * 4 * Copyright (c) 2013 Red Hat, Inc., 5 * 6 * Authors: 7 * Jeff Cody <jcody@redhat.com> 8 * 9 * This is based on the "VHDX Format Specification v1.00", published 8/25/2012 10 * by Microsoft: 11 * https://www.microsoft.com/en-us/download/details.aspx?id=34750 12 * 13 * This work is licensed under the terms of the GNU LGPL, version 2 or later. 14 * See the COPYING.LIB file in the top-level directory. 15 * 16 */ 17 18 #include "qemu-common.h" 19 #include "block/block_int.h" 20 #include "qemu/module.h" 21 #include "qemu/crc32c.h" 22 #include "block/vhdx.h" 23 #include "migration/migration.h" 24 25 #include <uuid/uuid.h> 26 #include <glib.h> 27 28 /* Options for VHDX creation */ 29 30 #define VHDX_BLOCK_OPT_LOG_SIZE "log_size" 31 #define VHDX_BLOCK_OPT_BLOCK_SIZE "block_size" 32 #define VHDX_BLOCK_OPT_ZERO "block_state_zero" 33 34 typedef enum VHDXImageType { 35 VHDX_TYPE_DYNAMIC = 0, 36 VHDX_TYPE_FIXED, 37 VHDX_TYPE_DIFFERENCING, /* Currently unsupported */ 38 } VHDXImageType; 39 40 /* Several metadata and region table data entries are identified by 41 * guids in a MS-specific GUID format. */ 42 43 44 /* ------- Known Region Table GUIDs ---------------------- */ 45 static const MSGUID bat_guid = { .data1 = 0x2dc27766, 46 .data2 = 0xf623, 47 .data3 = 0x4200, 48 .data4 = { 0x9d, 0x64, 0x11, 0x5e, 49 0x9b, 0xfd, 0x4a, 0x08} }; 50 51 static const MSGUID metadata_guid = { .data1 = 0x8b7ca206, 52 .data2 = 0x4790, 53 .data3 = 0x4b9a, 54 .data4 = { 0xb8, 0xfe, 0x57, 0x5f, 55 0x05, 0x0f, 0x88, 0x6e} }; 56 57 58 59 /* ------- Known Metadata Entry GUIDs ---------------------- */ 60 static const MSGUID file_param_guid = { .data1 = 0xcaa16737, 61 .data2 = 0xfa36, 62 .data3 = 0x4d43, 63 .data4 = { 0xb3, 0xb6, 0x33, 0xf0, 64 0xaa, 0x44, 0xe7, 0x6b} }; 65 66 static const MSGUID virtual_size_guid = { .data1 = 0x2FA54224, 67 .data2 = 0xcd1b, 68 .data3 = 0x4876, 69 .data4 = { 0xb2, 0x11, 0x5d, 0xbe, 70 0xd8, 0x3b, 0xf4, 0xb8} }; 71 72 static const MSGUID page83_guid = { .data1 = 0xbeca12ab, 73 .data2 = 0xb2e6, 74 .data3 = 0x4523, 75 .data4 = { 0x93, 0xef, 0xc3, 0x09, 76 0xe0, 0x00, 0xc7, 0x46} }; 77 78 79 static const MSGUID phys_sector_guid = { .data1 = 0xcda348c7, 80 .data2 = 0x445d, 81 .data3 = 0x4471, 82 .data4 = { 0x9c, 0xc9, 0xe9, 0x88, 83 0x52, 0x51, 0xc5, 0x56} }; 84 85 static const MSGUID parent_locator_guid = { .data1 = 0xa8d35f2d, 86 .data2 = 0xb30b, 87 .data3 = 0x454d, 88 .data4 = { 0xab, 0xf7, 0xd3, 89 0xd8, 0x48, 0x34, 90 0xab, 0x0c} }; 91 92 static const MSGUID logical_sector_guid = { .data1 = 0x8141bf1d, 93 .data2 = 0xa96f, 94 .data3 = 0x4709, 95 .data4 = { 0xba, 0x47, 0xf2, 96 0x33, 0xa8, 0xfa, 97 0xab, 0x5f} }; 98 99 /* Each parent type must have a valid GUID; this is for parent images 100 * of type 'VHDX'. If we were to allow e.g. a QCOW2 parent, we would 101 * need to make up our own QCOW2 GUID type */ 102 static const MSGUID parent_vhdx_guid __attribute__((unused)) 103 = { .data1 = 0xb04aefb7, 104 .data2 = 0xd19e, 105 .data3 = 0x4a81, 106 .data4 = { 0xb7, 0x89, 0x25, 0xb8, 107 0xe9, 0x44, 0x59, 0x13} }; 108 109 110 #define META_FILE_PARAMETER_PRESENT 0x01 111 #define META_VIRTUAL_DISK_SIZE_PRESENT 0x02 112 #define META_PAGE_83_PRESENT 0x04 113 #define META_LOGICAL_SECTOR_SIZE_PRESENT 0x08 114 #define META_PHYS_SECTOR_SIZE_PRESENT 0x10 115 #define META_PARENT_LOCATOR_PRESENT 0x20 116 117 #define META_ALL_PRESENT \ 118 (META_FILE_PARAMETER_PRESENT | META_VIRTUAL_DISK_SIZE_PRESENT | \ 119 META_PAGE_83_PRESENT | META_LOGICAL_SECTOR_SIZE_PRESENT | \ 120 META_PHYS_SECTOR_SIZE_PRESENT) 121 122 123 typedef struct VHDXSectorInfo { 124 uint32_t bat_idx; /* BAT entry index */ 125 uint32_t sectors_avail; /* sectors available in payload block */ 126 uint32_t bytes_left; /* bytes left in the block after data to r/w */ 127 uint32_t bytes_avail; /* bytes available in payload block */ 128 uint64_t file_offset; /* absolute offset in bytes, in file */ 129 uint64_t block_offset; /* block offset, in bytes */ 130 } VHDXSectorInfo; 131 132 /* Calculates new checksum. 133 * 134 * Zero is substituted during crc calculation for the original crc field 135 * crc_offset: byte offset in buf of the buffer crc 136 * buf: buffer pointer 137 * size: size of buffer (must be > crc_offset+4) 138 * 139 * Note: The buffer should have all multi-byte data in little-endian format, 140 * and the resulting checksum is in little endian format. 141 */ 142 uint32_t vhdx_update_checksum(uint8_t *buf, size_t size, int crc_offset) 143 { 144 uint32_t crc; 145 146 assert(buf != NULL); 147 assert(size > (crc_offset + sizeof(crc))); 148 149 memset(buf + crc_offset, 0, sizeof(crc)); 150 crc = crc32c(0xffffffff, buf, size); 151 cpu_to_le32s(&crc); 152 memcpy(buf + crc_offset, &crc, sizeof(crc)); 153 154 return crc; 155 } 156 157 uint32_t vhdx_checksum_calc(uint32_t crc, uint8_t *buf, size_t size, 158 int crc_offset) 159 { 160 uint32_t crc_new; 161 uint32_t crc_orig; 162 assert(buf != NULL); 163 164 if (crc_offset > 0) { 165 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 166 memset(buf + crc_offset, 0, sizeof(crc_orig)); 167 } 168 169 crc_new = crc32c(crc, buf, size); 170 if (crc_offset > 0) { 171 memcpy(buf + crc_offset, &crc_orig, sizeof(crc_orig)); 172 } 173 174 return crc_new; 175 } 176 177 /* Validates the checksum of the buffer, with an in-place CRC. 178 * 179 * Zero is substituted during crc calculation for the original crc field, 180 * and the crc field is restored afterwards. But the buffer will be modifed 181 * during the calculation, so this may not be not suitable for multi-threaded 182 * use. 183 * 184 * crc_offset: byte offset in buf of the buffer crc 185 * buf: buffer pointer 186 * size: size of buffer (must be > crc_offset+4) 187 * 188 * returns true if checksum is valid, false otherwise 189 */ 190 bool vhdx_checksum_is_valid(uint8_t *buf, size_t size, int crc_offset) 191 { 192 uint32_t crc_orig; 193 uint32_t crc; 194 195 assert(buf != NULL); 196 assert(size > (crc_offset + 4)); 197 198 memcpy(&crc_orig, buf + crc_offset, sizeof(crc_orig)); 199 crc_orig = le32_to_cpu(crc_orig); 200 201 crc = vhdx_checksum_calc(0xffffffff, buf, size, crc_offset); 202 203 return crc == crc_orig; 204 } 205 206 207 /* 208 * This generates a UUID that is compliant with the MS GUIDs used 209 * in the VHDX spec (and elsewhere). 210 */ 211 void vhdx_guid_generate(MSGUID *guid) 212 { 213 uuid_t uuid; 214 assert(guid != NULL); 215 216 uuid_generate(uuid); 217 memcpy(guid, uuid, sizeof(MSGUID)); 218 } 219 220 /* Check for region overlaps inside the VHDX image */ 221 static int vhdx_region_check(BDRVVHDXState *s, uint64_t start, uint64_t length) 222 { 223 int ret = 0; 224 uint64_t end; 225 VHDXRegionEntry *r; 226 227 end = start + length; 228 QLIST_FOREACH(r, &s->regions, entries) { 229 if (!((start >= r->end) || (end <= r->start))) { 230 ret = -EINVAL; 231 goto exit; 232 } 233 } 234 235 exit: 236 return ret; 237 } 238 239 /* Register a region for future checks */ 240 static void vhdx_region_register(BDRVVHDXState *s, 241 uint64_t start, uint64_t length) 242 { 243 VHDXRegionEntry *r; 244 245 r = g_malloc0(sizeof(*r)); 246 247 r->start = start; 248 r->end = start + length; 249 250 QLIST_INSERT_HEAD(&s->regions, r, entries); 251 } 252 253 /* Free all registered regions */ 254 static void vhdx_region_unregister_all(BDRVVHDXState *s) 255 { 256 VHDXRegionEntry *r, *r_next; 257 258 QLIST_FOREACH_SAFE(r, &s->regions, entries, r_next) { 259 QLIST_REMOVE(r, entries); 260 g_free(r); 261 } 262 } 263 264 static void vhdx_set_shift_bits(BDRVVHDXState *s) 265 { 266 s->logical_sector_size_bits = 31 - clz32(s->logical_sector_size); 267 s->sectors_per_block_bits = 31 - clz32(s->sectors_per_block); 268 s->chunk_ratio_bits = 63 - clz64(s->chunk_ratio); 269 s->block_size_bits = 31 - clz32(s->block_size); 270 } 271 272 /* 273 * Per the MS VHDX Specification, for every VHDX file: 274 * - The header section is fixed size - 1 MB 275 * - The header section is always the first "object" 276 * - The first 64KB of the header is the File Identifier 277 * - The first uint64 (8 bytes) is the VHDX Signature ("vhdxfile") 278 * - The following 512 bytes constitute a UTF-16 string identifiying the 279 * software that created the file, and is optional and diagnostic only. 280 * 281 * Therefore, we probe by looking for the vhdxfile signature "vhdxfile" 282 */ 283 static int vhdx_probe(const uint8_t *buf, int buf_size, const char *filename) 284 { 285 if (buf_size >= 8 && !memcmp(buf, "vhdxfile", 8)) { 286 return 100; 287 } 288 return 0; 289 } 290 291 /* 292 * Writes the header to the specified offset. 293 * 294 * This will optionally read in buffer data from disk (otherwise zero-fill), 295 * and then update the header checksum. Header is converted to proper 296 * endianness before being written to the specified file offset 297 */ 298 static int vhdx_write_header(BlockDriverState *bs_file, VHDXHeader *hdr, 299 uint64_t offset, bool read) 300 { 301 uint8_t *buffer = NULL; 302 int ret; 303 VHDXHeader *header_le; 304 305 assert(bs_file != NULL); 306 assert(hdr != NULL); 307 308 /* the header checksum is not over just the packed size of VHDXHeader, 309 * but rather over the entire 'reserved' range for the header, which is 310 * 4KB (VHDX_HEADER_SIZE). */ 311 312 buffer = qemu_blockalign(bs_file, VHDX_HEADER_SIZE); 313 if (read) { 314 /* if true, we can't assume the extra reserved bytes are 0 */ 315 ret = bdrv_pread(bs_file, offset, buffer, VHDX_HEADER_SIZE); 316 if (ret < 0) { 317 goto exit; 318 } 319 } else { 320 memset(buffer, 0, VHDX_HEADER_SIZE); 321 } 322 323 /* overwrite the actual VHDXHeader portion */ 324 header_le = (VHDXHeader *)buffer; 325 memcpy(header_le, hdr, sizeof(VHDXHeader)); 326 vhdx_header_le_export(hdr, header_le); 327 vhdx_update_checksum(buffer, VHDX_HEADER_SIZE, 328 offsetof(VHDXHeader, checksum)); 329 ret = bdrv_pwrite_sync(bs_file, offset, header_le, sizeof(VHDXHeader)); 330 331 exit: 332 qemu_vfree(buffer); 333 return ret; 334 } 335 336 /* Update the VHDX headers 337 * 338 * This follows the VHDX spec procedures for header updates. 339 * 340 * - non-current header is updated with largest sequence number 341 */ 342 static int vhdx_update_header(BlockDriverState *bs, BDRVVHDXState *s, 343 bool generate_data_write_guid, MSGUID *log_guid) 344 { 345 int ret = 0; 346 int hdr_idx = 0; 347 uint64_t header_offset = VHDX_HEADER1_OFFSET; 348 349 VHDXHeader *active_header; 350 VHDXHeader *inactive_header; 351 352 /* operate on the non-current header */ 353 if (s->curr_header == 0) { 354 hdr_idx = 1; 355 header_offset = VHDX_HEADER2_OFFSET; 356 } 357 358 active_header = s->headers[s->curr_header]; 359 inactive_header = s->headers[hdr_idx]; 360 361 inactive_header->sequence_number = active_header->sequence_number + 1; 362 363 /* a new file guid must be generated before any file write, including 364 * headers */ 365 inactive_header->file_write_guid = s->session_guid; 366 367 /* a new data guid only needs to be generated before any guest-visible 368 * writes (i.e. something observable via virtual disk read) */ 369 if (generate_data_write_guid) { 370 vhdx_guid_generate(&inactive_header->data_write_guid); 371 } 372 373 /* update the log guid if present */ 374 if (log_guid) { 375 inactive_header->log_guid = *log_guid; 376 } 377 378 ret = vhdx_write_header(bs->file->bs, inactive_header, header_offset, true); 379 if (ret < 0) { 380 goto exit; 381 } 382 s->curr_header = hdr_idx; 383 384 exit: 385 return ret; 386 } 387 388 /* 389 * The VHDX spec calls for header updates to be performed twice, so that both 390 * the current and non-current header have valid info 391 */ 392 int vhdx_update_headers(BlockDriverState *bs, BDRVVHDXState *s, 393 bool generate_data_write_guid, MSGUID *log_guid) 394 { 395 int ret; 396 397 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 398 if (ret < 0) { 399 return ret; 400 } 401 ret = vhdx_update_header(bs, s, generate_data_write_guid, log_guid); 402 return ret; 403 } 404 405 /* opens the specified header block from the VHDX file header section */ 406 static void vhdx_parse_header(BlockDriverState *bs, BDRVVHDXState *s, 407 Error **errp) 408 { 409 int ret; 410 VHDXHeader *header1; 411 VHDXHeader *header2; 412 bool h1_valid = false; 413 bool h2_valid = false; 414 uint64_t h1_seq = 0; 415 uint64_t h2_seq = 0; 416 uint8_t *buffer; 417 418 /* header1 & header2 are freed in vhdx_close() */ 419 header1 = qemu_blockalign(bs, sizeof(VHDXHeader)); 420 header2 = qemu_blockalign(bs, sizeof(VHDXHeader)); 421 422 buffer = qemu_blockalign(bs, VHDX_HEADER_SIZE); 423 424 s->headers[0] = header1; 425 s->headers[1] = header2; 426 427 /* We have to read the whole VHDX_HEADER_SIZE instead of 428 * sizeof(VHDXHeader), because the checksum is over the whole 429 * region */ 430 ret = bdrv_pread(bs->file->bs, VHDX_HEADER1_OFFSET, buffer, 431 VHDX_HEADER_SIZE); 432 if (ret < 0) { 433 goto fail; 434 } 435 /* copy over just the relevant portion that we need */ 436 memcpy(header1, buffer, sizeof(VHDXHeader)); 437 438 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 439 vhdx_header_le_import(header1); 440 if (header1->signature == VHDX_HEADER_SIGNATURE && 441 header1->version == 1) { 442 h1_seq = header1->sequence_number; 443 h1_valid = true; 444 } 445 } 446 447 ret = bdrv_pread(bs->file->bs, VHDX_HEADER2_OFFSET, buffer, 448 VHDX_HEADER_SIZE); 449 if (ret < 0) { 450 goto fail; 451 } 452 /* copy over just the relevant portion that we need */ 453 memcpy(header2, buffer, sizeof(VHDXHeader)); 454 455 if (vhdx_checksum_is_valid(buffer, VHDX_HEADER_SIZE, 4)) { 456 vhdx_header_le_import(header2); 457 if (header2->signature == VHDX_HEADER_SIGNATURE && 458 header2->version == 1) { 459 h2_seq = header2->sequence_number; 460 h2_valid = true; 461 } 462 } 463 464 /* If there is only 1 valid header (or no valid headers), we 465 * don't care what the sequence numbers are */ 466 if (h1_valid && !h2_valid) { 467 s->curr_header = 0; 468 } else if (!h1_valid && h2_valid) { 469 s->curr_header = 1; 470 } else if (!h1_valid && !h2_valid) { 471 goto fail; 472 } else { 473 /* If both headers are valid, then we choose the active one by the 474 * highest sequence number. If the sequence numbers are equal, that is 475 * invalid */ 476 if (h1_seq > h2_seq) { 477 s->curr_header = 0; 478 } else if (h2_seq > h1_seq) { 479 s->curr_header = 1; 480 } else { 481 /* The Microsoft Disk2VHD tool will create 2 identical 482 * headers, with identical sequence numbers. If the headers are 483 * identical, don't consider the file corrupt */ 484 if (!memcmp(header1, header2, sizeof(VHDXHeader))) { 485 s->curr_header = 0; 486 } else { 487 goto fail; 488 } 489 } 490 } 491 492 vhdx_region_register(s, s->headers[s->curr_header]->log_offset, 493 s->headers[s->curr_header]->log_length); 494 goto exit; 495 496 fail: 497 error_setg_errno(errp, -ret, "No valid VHDX header found"); 498 qemu_vfree(header1); 499 qemu_vfree(header2); 500 s->headers[0] = NULL; 501 s->headers[1] = NULL; 502 exit: 503 qemu_vfree(buffer); 504 } 505 506 507 static int vhdx_open_region_tables(BlockDriverState *bs, BDRVVHDXState *s) 508 { 509 int ret = 0; 510 uint8_t *buffer; 511 int offset = 0; 512 VHDXRegionTableEntry rt_entry; 513 uint32_t i; 514 bool bat_rt_found = false; 515 bool metadata_rt_found = false; 516 517 /* We have to read the whole 64KB block, because the crc32 is over the 518 * whole block */ 519 buffer = qemu_blockalign(bs, VHDX_HEADER_BLOCK_SIZE); 520 521 ret = bdrv_pread(bs->file->bs, VHDX_REGION_TABLE_OFFSET, buffer, 522 VHDX_HEADER_BLOCK_SIZE); 523 if (ret < 0) { 524 goto fail; 525 } 526 memcpy(&s->rt, buffer, sizeof(s->rt)); 527 offset += sizeof(s->rt); 528 529 if (!vhdx_checksum_is_valid(buffer, VHDX_HEADER_BLOCK_SIZE, 4)) { 530 ret = -EINVAL; 531 goto fail; 532 } 533 534 vhdx_region_header_le_import(&s->rt); 535 536 if (s->rt.signature != VHDX_REGION_SIGNATURE) { 537 ret = -EINVAL; 538 goto fail; 539 } 540 541 542 /* Per spec, maximum region table entry count is 2047 */ 543 if (s->rt.entry_count > 2047) { 544 ret = -EINVAL; 545 goto fail; 546 } 547 548 for (i = 0; i < s->rt.entry_count; i++) { 549 memcpy(&rt_entry, buffer + offset, sizeof(rt_entry)); 550 offset += sizeof(rt_entry); 551 552 vhdx_region_entry_le_import(&rt_entry); 553 554 /* check for region overlap between these entries, and any 555 * other memory regions in the file */ 556 ret = vhdx_region_check(s, rt_entry.file_offset, rt_entry.length); 557 if (ret < 0) { 558 goto fail; 559 } 560 561 vhdx_region_register(s, rt_entry.file_offset, rt_entry.length); 562 563 /* see if we recognize the entry */ 564 if (guid_eq(rt_entry.guid, bat_guid)) { 565 /* must be unique; if we have already found it this is invalid */ 566 if (bat_rt_found) { 567 ret = -EINVAL; 568 goto fail; 569 } 570 bat_rt_found = true; 571 s->bat_rt = rt_entry; 572 continue; 573 } 574 575 if (guid_eq(rt_entry.guid, metadata_guid)) { 576 /* must be unique; if we have already found it this is invalid */ 577 if (metadata_rt_found) { 578 ret = -EINVAL; 579 goto fail; 580 } 581 metadata_rt_found = true; 582 s->metadata_rt = rt_entry; 583 continue; 584 } 585 586 if (rt_entry.data_bits & VHDX_REGION_ENTRY_REQUIRED) { 587 /* cannot read vhdx file - required region table entry that 588 * we do not understand. per spec, we must fail to open */ 589 ret = -ENOTSUP; 590 goto fail; 591 } 592 } 593 594 if (!bat_rt_found || !metadata_rt_found) { 595 ret = -EINVAL; 596 goto fail; 597 } 598 599 ret = 0; 600 601 fail: 602 qemu_vfree(buffer); 603 return ret; 604 } 605 606 607 608 /* Metadata initial parser 609 * 610 * This loads all the metadata entry fields. This may cause additional 611 * fields to be processed (e.g. parent locator, etc..). 612 * 613 * There are 5 Metadata items that are always required: 614 * - File Parameters (block size, has a parent) 615 * - Virtual Disk Size (size, in bytes, of the virtual drive) 616 * - Page 83 Data (scsi page 83 guid) 617 * - Logical Sector Size (logical sector size in bytes, either 512 or 618 * 4096. We only support 512 currently) 619 * - Physical Sector Size (512 or 4096) 620 * 621 * Also, if the File Parameters indicate this is a differencing file, 622 * we must also look for the Parent Locator metadata item. 623 */ 624 static int vhdx_parse_metadata(BlockDriverState *bs, BDRVVHDXState *s) 625 { 626 int ret = 0; 627 uint8_t *buffer; 628 int offset = 0; 629 uint32_t i = 0; 630 VHDXMetadataTableEntry md_entry; 631 632 buffer = qemu_blockalign(bs, VHDX_METADATA_TABLE_MAX_SIZE); 633 634 ret = bdrv_pread(bs->file->bs, s->metadata_rt.file_offset, buffer, 635 VHDX_METADATA_TABLE_MAX_SIZE); 636 if (ret < 0) { 637 goto exit; 638 } 639 memcpy(&s->metadata_hdr, buffer, sizeof(s->metadata_hdr)); 640 offset += sizeof(s->metadata_hdr); 641 642 vhdx_metadata_header_le_import(&s->metadata_hdr); 643 644 if (s->metadata_hdr.signature != VHDX_METADATA_SIGNATURE) { 645 ret = -EINVAL; 646 goto exit; 647 } 648 649 s->metadata_entries.present = 0; 650 651 if ((s->metadata_hdr.entry_count * sizeof(md_entry)) > 652 (VHDX_METADATA_TABLE_MAX_SIZE - offset)) { 653 ret = -EINVAL; 654 goto exit; 655 } 656 657 for (i = 0; i < s->metadata_hdr.entry_count; i++) { 658 memcpy(&md_entry, buffer + offset, sizeof(md_entry)); 659 offset += sizeof(md_entry); 660 661 vhdx_metadata_entry_le_import(&md_entry); 662 663 if (guid_eq(md_entry.item_id, file_param_guid)) { 664 if (s->metadata_entries.present & META_FILE_PARAMETER_PRESENT) { 665 ret = -EINVAL; 666 goto exit; 667 } 668 s->metadata_entries.file_parameters_entry = md_entry; 669 s->metadata_entries.present |= META_FILE_PARAMETER_PRESENT; 670 continue; 671 } 672 673 if (guid_eq(md_entry.item_id, virtual_size_guid)) { 674 if (s->metadata_entries.present & META_VIRTUAL_DISK_SIZE_PRESENT) { 675 ret = -EINVAL; 676 goto exit; 677 } 678 s->metadata_entries.virtual_disk_size_entry = md_entry; 679 s->metadata_entries.present |= META_VIRTUAL_DISK_SIZE_PRESENT; 680 continue; 681 } 682 683 if (guid_eq(md_entry.item_id, page83_guid)) { 684 if (s->metadata_entries.present & META_PAGE_83_PRESENT) { 685 ret = -EINVAL; 686 goto exit; 687 } 688 s->metadata_entries.page83_data_entry = md_entry; 689 s->metadata_entries.present |= META_PAGE_83_PRESENT; 690 continue; 691 } 692 693 if (guid_eq(md_entry.item_id, logical_sector_guid)) { 694 if (s->metadata_entries.present & 695 META_LOGICAL_SECTOR_SIZE_PRESENT) { 696 ret = -EINVAL; 697 goto exit; 698 } 699 s->metadata_entries.logical_sector_size_entry = md_entry; 700 s->metadata_entries.present |= META_LOGICAL_SECTOR_SIZE_PRESENT; 701 continue; 702 } 703 704 if (guid_eq(md_entry.item_id, phys_sector_guid)) { 705 if (s->metadata_entries.present & META_PHYS_SECTOR_SIZE_PRESENT) { 706 ret = -EINVAL; 707 goto exit; 708 } 709 s->metadata_entries.phys_sector_size_entry = md_entry; 710 s->metadata_entries.present |= META_PHYS_SECTOR_SIZE_PRESENT; 711 continue; 712 } 713 714 if (guid_eq(md_entry.item_id, parent_locator_guid)) { 715 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 716 ret = -EINVAL; 717 goto exit; 718 } 719 s->metadata_entries.parent_locator_entry = md_entry; 720 s->metadata_entries.present |= META_PARENT_LOCATOR_PRESENT; 721 continue; 722 } 723 724 if (md_entry.data_bits & VHDX_META_FLAGS_IS_REQUIRED) { 725 /* cannot read vhdx file - required region table entry that 726 * we do not understand. per spec, we must fail to open */ 727 ret = -ENOTSUP; 728 goto exit; 729 } 730 } 731 732 if (s->metadata_entries.present != META_ALL_PRESENT) { 733 ret = -ENOTSUP; 734 goto exit; 735 } 736 737 ret = bdrv_pread(bs->file->bs, 738 s->metadata_entries.file_parameters_entry.offset 739 + s->metadata_rt.file_offset, 740 &s->params, 741 sizeof(s->params)); 742 743 if (ret < 0) { 744 goto exit; 745 } 746 747 le32_to_cpus(&s->params.block_size); 748 le32_to_cpus(&s->params.data_bits); 749 750 751 /* We now have the file parameters, so we can tell if this is a 752 * differencing file (i.e.. has_parent), is dynamic or fixed 753 * sized (leave_blocks_allocated), and the block size */ 754 755 /* The parent locator required iff the file parameters has_parent set */ 756 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 757 if (s->metadata_entries.present & META_PARENT_LOCATOR_PRESENT) { 758 /* TODO: parse parent locator fields */ 759 ret = -ENOTSUP; /* temp, until differencing files are supported */ 760 goto exit; 761 } else { 762 /* if has_parent is set, but there is not parent locator present, 763 * then that is an invalid combination */ 764 ret = -EINVAL; 765 goto exit; 766 } 767 } 768 769 /* determine virtual disk size, logical sector size, 770 * and phys sector size */ 771 772 ret = bdrv_pread(bs->file->bs, 773 s->metadata_entries.virtual_disk_size_entry.offset 774 + s->metadata_rt.file_offset, 775 &s->virtual_disk_size, 776 sizeof(uint64_t)); 777 if (ret < 0) { 778 goto exit; 779 } 780 ret = bdrv_pread(bs->file->bs, 781 s->metadata_entries.logical_sector_size_entry.offset 782 + s->metadata_rt.file_offset, 783 &s->logical_sector_size, 784 sizeof(uint32_t)); 785 if (ret < 0) { 786 goto exit; 787 } 788 ret = bdrv_pread(bs->file->bs, 789 s->metadata_entries.phys_sector_size_entry.offset 790 + s->metadata_rt.file_offset, 791 &s->physical_sector_size, 792 sizeof(uint32_t)); 793 if (ret < 0) { 794 goto exit; 795 } 796 797 le64_to_cpus(&s->virtual_disk_size); 798 le32_to_cpus(&s->logical_sector_size); 799 le32_to_cpus(&s->physical_sector_size); 800 801 if (s->params.block_size < VHDX_BLOCK_SIZE_MIN || 802 s->params.block_size > VHDX_BLOCK_SIZE_MAX) { 803 ret = -EINVAL; 804 goto exit; 805 } 806 807 /* only 2 supported sector sizes */ 808 if (s->logical_sector_size != 512 && s->logical_sector_size != 4096) { 809 ret = -EINVAL; 810 goto exit; 811 } 812 813 /* Both block_size and sector_size are guaranteed powers of 2, below. 814 Due to range checks above, s->sectors_per_block can never be < 256 */ 815 s->sectors_per_block = s->params.block_size / s->logical_sector_size; 816 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 817 (uint64_t)s->logical_sector_size / 818 (uint64_t)s->params.block_size; 819 820 /* These values are ones we will want to use for division / multiplication 821 * later on, and they are all guaranteed (per the spec) to be powers of 2, 822 * so we can take advantage of that for shift operations during 823 * reads/writes */ 824 if (s->logical_sector_size & (s->logical_sector_size - 1)) { 825 ret = -EINVAL; 826 goto exit; 827 } 828 if (s->sectors_per_block & (s->sectors_per_block - 1)) { 829 ret = -EINVAL; 830 goto exit; 831 } 832 if (s->chunk_ratio & (s->chunk_ratio - 1)) { 833 ret = -EINVAL; 834 goto exit; 835 } 836 s->block_size = s->params.block_size; 837 if (s->block_size & (s->block_size - 1)) { 838 ret = -EINVAL; 839 goto exit; 840 } 841 842 vhdx_set_shift_bits(s); 843 844 ret = 0; 845 846 exit: 847 qemu_vfree(buffer); 848 return ret; 849 } 850 851 /* 852 * Calculate the number of BAT entries, including sector 853 * bitmap entries. 854 */ 855 static void vhdx_calc_bat_entries(BDRVVHDXState *s) 856 { 857 uint32_t data_blocks_cnt, bitmap_blocks_cnt; 858 859 data_blocks_cnt = s->virtual_disk_size >> s->block_size_bits; 860 if (s->virtual_disk_size - (data_blocks_cnt << s->block_size_bits)) { 861 data_blocks_cnt++; 862 } 863 bitmap_blocks_cnt = data_blocks_cnt >> s->chunk_ratio_bits; 864 if (data_blocks_cnt - (bitmap_blocks_cnt << s->chunk_ratio_bits)) { 865 bitmap_blocks_cnt++; 866 } 867 868 if (s->parent_entries) { 869 s->bat_entries = bitmap_blocks_cnt * (s->chunk_ratio + 1); 870 } else { 871 s->bat_entries = data_blocks_cnt + 872 ((data_blocks_cnt - 1) >> s->chunk_ratio_bits); 873 } 874 875 } 876 877 static void vhdx_close(BlockDriverState *bs) 878 { 879 BDRVVHDXState *s = bs->opaque; 880 qemu_vfree(s->headers[0]); 881 s->headers[0] = NULL; 882 qemu_vfree(s->headers[1]); 883 s->headers[1] = NULL; 884 qemu_vfree(s->bat); 885 s->bat = NULL; 886 qemu_vfree(s->parent_entries); 887 s->parent_entries = NULL; 888 migrate_del_blocker(s->migration_blocker); 889 error_free(s->migration_blocker); 890 qemu_vfree(s->log.hdr); 891 s->log.hdr = NULL; 892 vhdx_region_unregister_all(s); 893 } 894 895 static int vhdx_open(BlockDriverState *bs, QDict *options, int flags, 896 Error **errp) 897 { 898 BDRVVHDXState *s = bs->opaque; 899 int ret = 0; 900 uint32_t i; 901 uint64_t signature; 902 Error *local_err = NULL; 903 904 s->bat = NULL; 905 s->first_visible_write = true; 906 907 qemu_co_mutex_init(&s->lock); 908 QLIST_INIT(&s->regions); 909 910 /* validate the file signature */ 911 ret = bdrv_pread(bs->file->bs, 0, &signature, sizeof(uint64_t)); 912 if (ret < 0) { 913 goto fail; 914 } 915 if (memcmp(&signature, "vhdxfile", 8)) { 916 ret = -EINVAL; 917 goto fail; 918 } 919 920 /* This is used for any header updates, for the file_write_guid. 921 * The spec dictates that a new value should be used for the first 922 * header update */ 923 vhdx_guid_generate(&s->session_guid); 924 925 vhdx_parse_header(bs, s, &local_err); 926 if (local_err != NULL) { 927 error_propagate(errp, local_err); 928 ret = -EINVAL; 929 goto fail; 930 } 931 932 ret = vhdx_parse_log(bs, s, &s->log_replayed_on_open, errp); 933 if (ret < 0) { 934 goto fail; 935 } 936 937 ret = vhdx_open_region_tables(bs, s); 938 if (ret < 0) { 939 goto fail; 940 } 941 942 ret = vhdx_parse_metadata(bs, s); 943 if (ret < 0) { 944 goto fail; 945 } 946 947 s->block_size = s->params.block_size; 948 949 /* the VHDX spec dictates that virtual_disk_size is always a multiple of 950 * logical_sector_size */ 951 bs->total_sectors = s->virtual_disk_size >> s->logical_sector_size_bits; 952 953 vhdx_calc_bat_entries(s); 954 955 s->bat_offset = s->bat_rt.file_offset; 956 957 if (s->bat_entries > s->bat_rt.length / sizeof(VHDXBatEntry)) { 958 /* BAT allocation is not large enough for all entries */ 959 ret = -EINVAL; 960 goto fail; 961 } 962 963 /* s->bat is freed in vhdx_close() */ 964 s->bat = qemu_try_blockalign(bs->file->bs, s->bat_rt.length); 965 if (s->bat == NULL) { 966 ret = -ENOMEM; 967 goto fail; 968 } 969 970 ret = bdrv_pread(bs->file->bs, s->bat_offset, s->bat, s->bat_rt.length); 971 if (ret < 0) { 972 goto fail; 973 } 974 975 uint64_t payblocks = s->chunk_ratio; 976 /* endian convert, and verify populated BAT field file offsets against 977 * region table and log entries */ 978 for (i = 0; i < s->bat_entries; i++) { 979 le64_to_cpus(&s->bat[i]); 980 if (payblocks--) { 981 /* payload bat entries */ 982 if ((s->bat[i] & VHDX_BAT_STATE_BIT_MASK) == 983 PAYLOAD_BLOCK_FULLY_PRESENT) { 984 ret = vhdx_region_check(s, s->bat[i] & VHDX_BAT_FILE_OFF_MASK, 985 s->block_size); 986 if (ret < 0) { 987 goto fail; 988 } 989 } 990 } else { 991 payblocks = s->chunk_ratio; 992 /* Once differencing files are supported, verify sector bitmap 993 * blocks here */ 994 } 995 } 996 997 if (flags & BDRV_O_RDWR) { 998 ret = vhdx_update_headers(bs, s, false, NULL); 999 if (ret < 0) { 1000 goto fail; 1001 } 1002 } 1003 1004 /* TODO: differencing files */ 1005 1006 /* Disable migration when VHDX images are used */ 1007 error_setg(&s->migration_blocker, "The vhdx format used by node '%s' " 1008 "does not support live migration", 1009 bdrv_get_device_or_node_name(bs)); 1010 migrate_add_blocker(s->migration_blocker); 1011 1012 return 0; 1013 fail: 1014 vhdx_close(bs); 1015 return ret; 1016 } 1017 1018 static int vhdx_reopen_prepare(BDRVReopenState *state, 1019 BlockReopenQueue *queue, Error **errp) 1020 { 1021 return 0; 1022 } 1023 1024 1025 /* 1026 * Perform sector to block offset translations, to get various 1027 * sector and file offsets into the image. See VHDXSectorInfo 1028 */ 1029 static void vhdx_block_translate(BDRVVHDXState *s, int64_t sector_num, 1030 int nb_sectors, VHDXSectorInfo *sinfo) 1031 { 1032 uint32_t block_offset; 1033 1034 sinfo->bat_idx = sector_num >> s->sectors_per_block_bits; 1035 /* effectively a modulo - this gives us the offset into the block 1036 * (in sector sizes) for our sector number */ 1037 block_offset = sector_num - (sinfo->bat_idx << s->sectors_per_block_bits); 1038 /* the chunk ratio gives us the interleaving of the sector 1039 * bitmaps, so we need to advance our page block index by the 1040 * sector bitmaps entry number */ 1041 sinfo->bat_idx += sinfo->bat_idx >> s->chunk_ratio_bits; 1042 1043 /* the number of sectors we can read/write in this cycle */ 1044 sinfo->sectors_avail = s->sectors_per_block - block_offset; 1045 1046 sinfo->bytes_left = sinfo->sectors_avail << s->logical_sector_size_bits; 1047 1048 if (sinfo->sectors_avail > nb_sectors) { 1049 sinfo->sectors_avail = nb_sectors; 1050 } 1051 1052 sinfo->bytes_avail = sinfo->sectors_avail << s->logical_sector_size_bits; 1053 1054 sinfo->file_offset = s->bat[sinfo->bat_idx] & VHDX_BAT_FILE_OFF_MASK; 1055 1056 sinfo->block_offset = block_offset << s->logical_sector_size_bits; 1057 1058 /* The file offset must be past the header section, so must be > 0 */ 1059 if (sinfo->file_offset == 0) { 1060 return; 1061 } 1062 1063 /* block offset is the offset in vhdx logical sectors, in 1064 * the payload data block. Convert that to a byte offset 1065 * in the block, and add in the payload data block offset 1066 * in the file, in bytes, to get the final read address */ 1067 1068 sinfo->file_offset += sinfo->block_offset; 1069 } 1070 1071 1072 static int vhdx_get_info(BlockDriverState *bs, BlockDriverInfo *bdi) 1073 { 1074 BDRVVHDXState *s = bs->opaque; 1075 1076 bdi->cluster_size = s->block_size; 1077 1078 bdi->unallocated_blocks_are_zero = 1079 (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) == 0; 1080 1081 return 0; 1082 } 1083 1084 1085 static coroutine_fn int vhdx_co_readv(BlockDriverState *bs, int64_t sector_num, 1086 int nb_sectors, QEMUIOVector *qiov) 1087 { 1088 BDRVVHDXState *s = bs->opaque; 1089 int ret = 0; 1090 VHDXSectorInfo sinfo; 1091 uint64_t bytes_done = 0; 1092 QEMUIOVector hd_qiov; 1093 1094 qemu_iovec_init(&hd_qiov, qiov->niov); 1095 1096 qemu_co_mutex_lock(&s->lock); 1097 1098 while (nb_sectors > 0) { 1099 /* We are a differencing file, so we need to inspect the sector bitmap 1100 * to see if we have the data or not */ 1101 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1102 /* not supported yet */ 1103 ret = -ENOTSUP; 1104 goto exit; 1105 } else { 1106 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1107 1108 qemu_iovec_reset(&hd_qiov); 1109 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, sinfo.bytes_avail); 1110 1111 /* check the payload block state */ 1112 switch (s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK) { 1113 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1114 case PAYLOAD_BLOCK_UNDEFINED: 1115 case PAYLOAD_BLOCK_UNMAPPED: 1116 case PAYLOAD_BLOCK_UNMAPPED_v095: 1117 case PAYLOAD_BLOCK_ZERO: 1118 /* return zero */ 1119 qemu_iovec_memset(&hd_qiov, 0, 0, sinfo.bytes_avail); 1120 break; 1121 case PAYLOAD_BLOCK_FULLY_PRESENT: 1122 qemu_co_mutex_unlock(&s->lock); 1123 ret = bdrv_co_readv(bs->file->bs, 1124 sinfo.file_offset >> BDRV_SECTOR_BITS, 1125 sinfo.sectors_avail, &hd_qiov); 1126 qemu_co_mutex_lock(&s->lock); 1127 if (ret < 0) { 1128 goto exit; 1129 } 1130 break; 1131 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1132 /* we don't yet support difference files, fall through 1133 * to error */ 1134 default: 1135 ret = -EIO; 1136 goto exit; 1137 break; 1138 } 1139 nb_sectors -= sinfo.sectors_avail; 1140 sector_num += sinfo.sectors_avail; 1141 bytes_done += sinfo.bytes_avail; 1142 } 1143 } 1144 ret = 0; 1145 exit: 1146 qemu_co_mutex_unlock(&s->lock); 1147 qemu_iovec_destroy(&hd_qiov); 1148 return ret; 1149 } 1150 1151 /* 1152 * Allocate a new payload block at the end of the file. 1153 * 1154 * Allocation will happen at 1MB alignment inside the file 1155 * 1156 * Returns the file offset start of the new payload block 1157 */ 1158 static int vhdx_allocate_block(BlockDriverState *bs, BDRVVHDXState *s, 1159 uint64_t *new_offset) 1160 { 1161 *new_offset = bdrv_getlength(bs->file->bs); 1162 1163 /* per the spec, the address for a block is in units of 1MB */ 1164 *new_offset = ROUND_UP(*new_offset, 1024 * 1024); 1165 1166 return bdrv_truncate(bs->file->bs, *new_offset + s->block_size); 1167 } 1168 1169 /* 1170 * Update the BAT table entry with the new file offset, and the new entry 1171 * state */ 1172 static void vhdx_update_bat_table_entry(BlockDriverState *bs, BDRVVHDXState *s, 1173 VHDXSectorInfo *sinfo, 1174 uint64_t *bat_entry_le, 1175 uint64_t *bat_offset, int state) 1176 { 1177 /* The BAT entry is a uint64, with 44 bits for the file offset in units of 1178 * 1MB, and 3 bits for the block state. */ 1179 if ((state == PAYLOAD_BLOCK_ZERO) || 1180 (state == PAYLOAD_BLOCK_UNDEFINED) || 1181 (state == PAYLOAD_BLOCK_NOT_PRESENT) || 1182 (state == PAYLOAD_BLOCK_UNMAPPED)) { 1183 s->bat[sinfo->bat_idx] = 0; /* For PAYLOAD_BLOCK_ZERO, the 1184 FileOffsetMB field is denoted as 1185 'reserved' in the v1.0 spec. If it is 1186 non-zero, MS Hyper-V will fail to read 1187 the disk image */ 1188 } else { 1189 s->bat[sinfo->bat_idx] = sinfo->file_offset; 1190 } 1191 1192 s->bat[sinfo->bat_idx] |= state & VHDX_BAT_STATE_BIT_MASK; 1193 1194 *bat_entry_le = cpu_to_le64(s->bat[sinfo->bat_idx]); 1195 *bat_offset = s->bat_offset + sinfo->bat_idx * sizeof(VHDXBatEntry); 1196 1197 } 1198 1199 /* Per the spec, on the first write of guest-visible data to the file the 1200 * data write guid must be updated in the header */ 1201 int vhdx_user_visible_write(BlockDriverState *bs, BDRVVHDXState *s) 1202 { 1203 int ret = 0; 1204 if (s->first_visible_write) { 1205 s->first_visible_write = false; 1206 ret = vhdx_update_headers(bs, s, true, NULL); 1207 } 1208 return ret; 1209 } 1210 1211 static coroutine_fn int vhdx_co_writev(BlockDriverState *bs, int64_t sector_num, 1212 int nb_sectors, QEMUIOVector *qiov) 1213 { 1214 int ret = -ENOTSUP; 1215 BDRVVHDXState *s = bs->opaque; 1216 VHDXSectorInfo sinfo; 1217 uint64_t bytes_done = 0; 1218 uint64_t bat_entry = 0; 1219 uint64_t bat_entry_offset = 0; 1220 QEMUIOVector hd_qiov; 1221 struct iovec iov1 = { 0 }; 1222 struct iovec iov2 = { 0 }; 1223 int sectors_to_write; 1224 int bat_state; 1225 uint64_t bat_prior_offset = 0; 1226 bool bat_update = false; 1227 1228 qemu_iovec_init(&hd_qiov, qiov->niov); 1229 1230 qemu_co_mutex_lock(&s->lock); 1231 1232 ret = vhdx_user_visible_write(bs, s); 1233 if (ret < 0) { 1234 goto exit; 1235 } 1236 1237 while (nb_sectors > 0) { 1238 bool use_zero_buffers = false; 1239 bat_update = false; 1240 if (s->params.data_bits & VHDX_PARAMS_HAS_PARENT) { 1241 /* not supported yet */ 1242 ret = -ENOTSUP; 1243 goto exit; 1244 } else { 1245 vhdx_block_translate(s, sector_num, nb_sectors, &sinfo); 1246 sectors_to_write = sinfo.sectors_avail; 1247 1248 qemu_iovec_reset(&hd_qiov); 1249 /* check the payload block state */ 1250 bat_state = s->bat[sinfo.bat_idx] & VHDX_BAT_STATE_BIT_MASK; 1251 switch (bat_state) { 1252 case PAYLOAD_BLOCK_ZERO: 1253 /* in this case, we need to preserve zero writes for 1254 * data that is not part of this write, so we must pad 1255 * the rest of the buffer to zeroes */ 1256 1257 /* if we are on a posix system with ftruncate() that extends 1258 * a file, then it is zero-filled for us. On Win32, the raw 1259 * layer uses SetFilePointer and SetFileEnd, which does not 1260 * zero fill AFAIK */ 1261 1262 /* Queue another write of zero buffers if the underlying file 1263 * does not zero-fill on file extension */ 1264 1265 if (bdrv_has_zero_init(bs->file->bs) == 0) { 1266 use_zero_buffers = true; 1267 1268 /* zero fill the front, if any */ 1269 if (sinfo.block_offset) { 1270 iov1.iov_len = sinfo.block_offset; 1271 iov1.iov_base = qemu_blockalign(bs, iov1.iov_len); 1272 memset(iov1.iov_base, 0, iov1.iov_len); 1273 qemu_iovec_concat_iov(&hd_qiov, &iov1, 1, 0, 1274 iov1.iov_len); 1275 sectors_to_write += iov1.iov_len >> BDRV_SECTOR_BITS; 1276 } 1277 1278 /* our actual data */ 1279 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1280 sinfo.bytes_avail); 1281 1282 /* zero fill the back, if any */ 1283 if ((sinfo.bytes_avail - sinfo.block_offset) < 1284 s->block_size) { 1285 iov2.iov_len = s->block_size - 1286 (sinfo.bytes_avail + sinfo.block_offset); 1287 iov2.iov_base = qemu_blockalign(bs, iov2.iov_len); 1288 memset(iov2.iov_base, 0, iov2.iov_len); 1289 qemu_iovec_concat_iov(&hd_qiov, &iov2, 1, 0, 1290 iov2.iov_len); 1291 sectors_to_write += iov2.iov_len >> BDRV_SECTOR_BITS; 1292 } 1293 } 1294 /* fall through */ 1295 case PAYLOAD_BLOCK_NOT_PRESENT: /* fall through */ 1296 case PAYLOAD_BLOCK_UNMAPPED: 1297 case PAYLOAD_BLOCK_UNMAPPED_v095: 1298 case PAYLOAD_BLOCK_UNDEFINED: 1299 bat_prior_offset = sinfo.file_offset; 1300 ret = vhdx_allocate_block(bs, s, &sinfo.file_offset); 1301 if (ret < 0) { 1302 goto exit; 1303 } 1304 /* once we support differencing files, this may also be 1305 * partially present */ 1306 /* update block state to the newly specified state */ 1307 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1308 &bat_entry_offset, 1309 PAYLOAD_BLOCK_FULLY_PRESENT); 1310 bat_update = true; 1311 /* since we just allocated a block, file_offset is the 1312 * beginning of the payload block. It needs to be the 1313 * write address, which includes the offset into the block */ 1314 if (!use_zero_buffers) { 1315 sinfo.file_offset += sinfo.block_offset; 1316 } 1317 /* fall through */ 1318 case PAYLOAD_BLOCK_FULLY_PRESENT: 1319 /* if the file offset address is in the header zone, 1320 * there is a problem */ 1321 if (sinfo.file_offset < (1024 * 1024)) { 1322 ret = -EFAULT; 1323 goto error_bat_restore; 1324 } 1325 1326 if (!use_zero_buffers) { 1327 qemu_iovec_concat(&hd_qiov, qiov, bytes_done, 1328 sinfo.bytes_avail); 1329 } 1330 /* block exists, so we can just overwrite it */ 1331 qemu_co_mutex_unlock(&s->lock); 1332 ret = bdrv_co_writev(bs->file->bs, 1333 sinfo.file_offset >> BDRV_SECTOR_BITS, 1334 sectors_to_write, &hd_qiov); 1335 qemu_co_mutex_lock(&s->lock); 1336 if (ret < 0) { 1337 goto error_bat_restore; 1338 } 1339 break; 1340 case PAYLOAD_BLOCK_PARTIALLY_PRESENT: 1341 /* we don't yet support difference files, fall through 1342 * to error */ 1343 default: 1344 ret = -EIO; 1345 goto exit; 1346 break; 1347 } 1348 1349 if (bat_update) { 1350 /* this will update the BAT entry into the log journal, and 1351 * then flush the log journal out to disk */ 1352 ret = vhdx_log_write_and_flush(bs, s, &bat_entry, 1353 sizeof(VHDXBatEntry), 1354 bat_entry_offset); 1355 if (ret < 0) { 1356 goto exit; 1357 } 1358 } 1359 1360 nb_sectors -= sinfo.sectors_avail; 1361 sector_num += sinfo.sectors_avail; 1362 bytes_done += sinfo.bytes_avail; 1363 1364 } 1365 } 1366 1367 goto exit; 1368 1369 error_bat_restore: 1370 if (bat_update) { 1371 /* keep metadata in sync, and restore the bat entry state 1372 * if error. */ 1373 sinfo.file_offset = bat_prior_offset; 1374 vhdx_update_bat_table_entry(bs, s, &sinfo, &bat_entry, 1375 &bat_entry_offset, bat_state); 1376 } 1377 exit: 1378 qemu_vfree(iov1.iov_base); 1379 qemu_vfree(iov2.iov_base); 1380 qemu_co_mutex_unlock(&s->lock); 1381 qemu_iovec_destroy(&hd_qiov); 1382 return ret; 1383 } 1384 1385 1386 1387 /* 1388 * Create VHDX Headers 1389 * 1390 * There are 2 headers, and the highest sequence number will represent 1391 * the active header 1392 */ 1393 static int vhdx_create_new_headers(BlockDriverState *bs, uint64_t image_size, 1394 uint32_t log_size) 1395 { 1396 int ret = 0; 1397 VHDXHeader *hdr = NULL; 1398 1399 hdr = g_new0(VHDXHeader, 1); 1400 1401 hdr->signature = VHDX_HEADER_SIGNATURE; 1402 hdr->sequence_number = g_random_int(); 1403 hdr->log_version = 0; 1404 hdr->version = 1; 1405 hdr->log_length = log_size; 1406 hdr->log_offset = VHDX_HEADER_SECTION_END; 1407 vhdx_guid_generate(&hdr->file_write_guid); 1408 vhdx_guid_generate(&hdr->data_write_guid); 1409 1410 ret = vhdx_write_header(bs, hdr, VHDX_HEADER1_OFFSET, false); 1411 if (ret < 0) { 1412 goto exit; 1413 } 1414 hdr->sequence_number++; 1415 ret = vhdx_write_header(bs, hdr, VHDX_HEADER2_OFFSET, false); 1416 if (ret < 0) { 1417 goto exit; 1418 } 1419 1420 exit: 1421 g_free(hdr); 1422 return ret; 1423 } 1424 1425 #define VHDX_METADATA_ENTRY_BUFFER_SIZE \ 1426 (sizeof(VHDXFileParameters) +\ 1427 sizeof(VHDXVirtualDiskSize) +\ 1428 sizeof(VHDXPage83Data) +\ 1429 sizeof(VHDXVirtualDiskLogicalSectorSize) +\ 1430 sizeof(VHDXVirtualDiskPhysicalSectorSize)) 1431 1432 /* 1433 * Create the Metadata entries. 1434 * 1435 * For more details on the entries, see section 3.5 (pg 29) in the 1436 * VHDX 1.00 specification. 1437 * 1438 * We support 5 metadata entries (all required by spec): 1439 * File Parameters, 1440 * Virtual Disk Size, 1441 * Page 83 Data, 1442 * Logical Sector Size, 1443 * Physical Sector Size 1444 * 1445 * The first 64KB of the Metadata section is reserved for the metadata 1446 * header and entries; beyond that, the metadata items themselves reside. 1447 */ 1448 static int vhdx_create_new_metadata(BlockDriverState *bs, 1449 uint64_t image_size, 1450 uint32_t block_size, 1451 uint32_t sector_size, 1452 uint64_t metadata_offset, 1453 VHDXImageType type) 1454 { 1455 int ret = 0; 1456 uint32_t offset = 0; 1457 void *buffer = NULL; 1458 void *entry_buffer; 1459 VHDXMetadataTableHeader *md_table; 1460 VHDXMetadataTableEntry *md_table_entry; 1461 1462 /* Metadata entries */ 1463 VHDXFileParameters *mt_file_params; 1464 VHDXVirtualDiskSize *mt_virtual_size; 1465 VHDXPage83Data *mt_page83; 1466 VHDXVirtualDiskLogicalSectorSize *mt_log_sector_size; 1467 VHDXVirtualDiskPhysicalSectorSize *mt_phys_sector_size; 1468 1469 entry_buffer = g_malloc0(VHDX_METADATA_ENTRY_BUFFER_SIZE); 1470 1471 mt_file_params = entry_buffer; 1472 offset += sizeof(VHDXFileParameters); 1473 mt_virtual_size = entry_buffer + offset; 1474 offset += sizeof(VHDXVirtualDiskSize); 1475 mt_page83 = entry_buffer + offset; 1476 offset += sizeof(VHDXPage83Data); 1477 mt_log_sector_size = entry_buffer + offset; 1478 offset += sizeof(VHDXVirtualDiskLogicalSectorSize); 1479 mt_phys_sector_size = entry_buffer + offset; 1480 1481 mt_file_params->block_size = cpu_to_le32(block_size); 1482 if (type == VHDX_TYPE_FIXED) { 1483 mt_file_params->data_bits |= VHDX_PARAMS_LEAVE_BLOCKS_ALLOCED; 1484 cpu_to_le32s(&mt_file_params->data_bits); 1485 } 1486 1487 vhdx_guid_generate(&mt_page83->page_83_data); 1488 cpu_to_leguids(&mt_page83->page_83_data); 1489 mt_virtual_size->virtual_disk_size = cpu_to_le64(image_size); 1490 mt_log_sector_size->logical_sector_size = cpu_to_le32(sector_size); 1491 mt_phys_sector_size->physical_sector_size = cpu_to_le32(sector_size); 1492 1493 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1494 md_table = buffer; 1495 1496 md_table->signature = VHDX_METADATA_SIGNATURE; 1497 md_table->entry_count = 5; 1498 vhdx_metadata_header_le_export(md_table); 1499 1500 1501 /* This will reference beyond the reserved table portion */ 1502 offset = 64 * KiB; 1503 1504 md_table_entry = buffer + sizeof(VHDXMetadataTableHeader); 1505 1506 md_table_entry[0].item_id = file_param_guid; 1507 md_table_entry[0].offset = offset; 1508 md_table_entry[0].length = sizeof(VHDXFileParameters); 1509 md_table_entry[0].data_bits |= VHDX_META_FLAGS_IS_REQUIRED; 1510 offset += md_table_entry[0].length; 1511 vhdx_metadata_entry_le_export(&md_table_entry[0]); 1512 1513 md_table_entry[1].item_id = virtual_size_guid; 1514 md_table_entry[1].offset = offset; 1515 md_table_entry[1].length = sizeof(VHDXVirtualDiskSize); 1516 md_table_entry[1].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1517 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1518 offset += md_table_entry[1].length; 1519 vhdx_metadata_entry_le_export(&md_table_entry[1]); 1520 1521 md_table_entry[2].item_id = page83_guid; 1522 md_table_entry[2].offset = offset; 1523 md_table_entry[2].length = sizeof(VHDXPage83Data); 1524 md_table_entry[2].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1525 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1526 offset += md_table_entry[2].length; 1527 vhdx_metadata_entry_le_export(&md_table_entry[2]); 1528 1529 md_table_entry[3].item_id = logical_sector_guid; 1530 md_table_entry[3].offset = offset; 1531 md_table_entry[3].length = sizeof(VHDXVirtualDiskLogicalSectorSize); 1532 md_table_entry[3].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1533 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1534 offset += md_table_entry[3].length; 1535 vhdx_metadata_entry_le_export(&md_table_entry[3]); 1536 1537 md_table_entry[4].item_id = phys_sector_guid; 1538 md_table_entry[4].offset = offset; 1539 md_table_entry[4].length = sizeof(VHDXVirtualDiskPhysicalSectorSize); 1540 md_table_entry[4].data_bits |= VHDX_META_FLAGS_IS_REQUIRED | 1541 VHDX_META_FLAGS_IS_VIRTUAL_DISK; 1542 vhdx_metadata_entry_le_export(&md_table_entry[4]); 1543 1544 ret = bdrv_pwrite(bs, metadata_offset, buffer, VHDX_HEADER_BLOCK_SIZE); 1545 if (ret < 0) { 1546 goto exit; 1547 } 1548 1549 ret = bdrv_pwrite(bs, metadata_offset + (64 * KiB), entry_buffer, 1550 VHDX_METADATA_ENTRY_BUFFER_SIZE); 1551 if (ret < 0) { 1552 goto exit; 1553 } 1554 1555 1556 exit: 1557 g_free(buffer); 1558 g_free(entry_buffer); 1559 return ret; 1560 } 1561 1562 /* This create the actual BAT itself. We currently only support 1563 * 'Dynamic' and 'Fixed' image types. 1564 * 1565 * Dynamic images: default state of the BAT is all zeroes. 1566 * 1567 * Fixed images: default state of the BAT is fully populated, with 1568 * file offsets and state PAYLOAD_BLOCK_FULLY_PRESENT. 1569 */ 1570 static int vhdx_create_bat(BlockDriverState *bs, BDRVVHDXState *s, 1571 uint64_t image_size, VHDXImageType type, 1572 bool use_zero_blocks, uint64_t file_offset, 1573 uint32_t length) 1574 { 1575 int ret = 0; 1576 uint64_t data_file_offset; 1577 uint64_t total_sectors = 0; 1578 uint64_t sector_num = 0; 1579 uint64_t unused; 1580 int block_state; 1581 VHDXSectorInfo sinfo; 1582 1583 assert(s->bat == NULL); 1584 1585 /* this gives a data start after BAT/bitmap entries, and well 1586 * past any metadata entries (with a 4 MB buffer for future 1587 * expansion */ 1588 data_file_offset = file_offset + length + 5 * MiB; 1589 total_sectors = image_size >> s->logical_sector_size_bits; 1590 1591 if (type == VHDX_TYPE_DYNAMIC) { 1592 /* All zeroes, so we can just extend the file - the end of the BAT 1593 * is the furthest thing we have written yet */ 1594 ret = bdrv_truncate(bs, data_file_offset); 1595 if (ret < 0) { 1596 goto exit; 1597 } 1598 } else if (type == VHDX_TYPE_FIXED) { 1599 ret = bdrv_truncate(bs, data_file_offset + image_size); 1600 if (ret < 0) { 1601 goto exit; 1602 } 1603 } else { 1604 ret = -ENOTSUP; 1605 goto exit; 1606 } 1607 1608 if (type == VHDX_TYPE_FIXED || 1609 use_zero_blocks || 1610 bdrv_has_zero_init(bs) == 0) { 1611 /* for a fixed file, the default BAT entry is not zero */ 1612 s->bat = g_try_malloc0(length); 1613 if (length && s->bat == NULL) { 1614 ret = -ENOMEM; 1615 goto exit; 1616 } 1617 block_state = type == VHDX_TYPE_FIXED ? PAYLOAD_BLOCK_FULLY_PRESENT : 1618 PAYLOAD_BLOCK_NOT_PRESENT; 1619 block_state = use_zero_blocks ? PAYLOAD_BLOCK_ZERO : block_state; 1620 /* fill the BAT by emulating sector writes of sectors_per_block size */ 1621 while (sector_num < total_sectors) { 1622 vhdx_block_translate(s, sector_num, s->sectors_per_block, &sinfo); 1623 sinfo.file_offset = data_file_offset + 1624 (sector_num << s->logical_sector_size_bits); 1625 sinfo.file_offset = ROUND_UP(sinfo.file_offset, MiB); 1626 vhdx_update_bat_table_entry(bs, s, &sinfo, &unused, &unused, 1627 block_state); 1628 cpu_to_le64s(&s->bat[sinfo.bat_idx]); 1629 sector_num += s->sectors_per_block; 1630 } 1631 ret = bdrv_pwrite(bs, file_offset, s->bat, length); 1632 if (ret < 0) { 1633 goto exit; 1634 } 1635 } 1636 1637 1638 1639 exit: 1640 g_free(s->bat); 1641 return ret; 1642 } 1643 1644 /* Creates the region table header, and region table entries. 1645 * There are 2 supported region table entries: BAT, and Metadata/ 1646 * 1647 * As the calculations for the BAT region table are also needed 1648 * to create the BAT itself, we will also cause the BAT to be 1649 * created. 1650 */ 1651 static int vhdx_create_new_region_table(BlockDriverState *bs, 1652 uint64_t image_size, 1653 uint32_t block_size, 1654 uint32_t sector_size, 1655 uint32_t log_size, 1656 bool use_zero_blocks, 1657 VHDXImageType type, 1658 uint64_t *metadata_offset) 1659 { 1660 int ret = 0; 1661 uint32_t offset = 0; 1662 void *buffer = NULL; 1663 uint64_t bat_file_offset; 1664 uint32_t bat_length; 1665 BDRVVHDXState *s = NULL; 1666 VHDXRegionTableHeader *region_table; 1667 VHDXRegionTableEntry *rt_bat; 1668 VHDXRegionTableEntry *rt_metadata; 1669 1670 assert(metadata_offset != NULL); 1671 1672 /* Populate enough of the BDRVVHDXState to be able to use the 1673 * pre-existing BAT calculation, translation, and update functions */ 1674 s = g_new0(BDRVVHDXState, 1); 1675 1676 s->chunk_ratio = (VHDX_MAX_SECTORS_PER_BLOCK) * 1677 (uint64_t) sector_size / (uint64_t) block_size; 1678 1679 s->sectors_per_block = block_size / sector_size; 1680 s->virtual_disk_size = image_size; 1681 s->block_size = block_size; 1682 s->logical_sector_size = sector_size; 1683 1684 vhdx_set_shift_bits(s); 1685 1686 vhdx_calc_bat_entries(s); 1687 1688 /* At this point the VHDX state is populated enough for creation */ 1689 1690 /* a single buffer is used so we can calculate the checksum over the 1691 * entire 64KB block */ 1692 buffer = g_malloc0(VHDX_HEADER_BLOCK_SIZE); 1693 region_table = buffer; 1694 offset += sizeof(VHDXRegionTableHeader); 1695 rt_bat = buffer + offset; 1696 offset += sizeof(VHDXRegionTableEntry); 1697 rt_metadata = buffer + offset; 1698 1699 region_table->signature = VHDX_REGION_SIGNATURE; 1700 region_table->entry_count = 2; /* BAT and Metadata */ 1701 1702 rt_bat->guid = bat_guid; 1703 rt_bat->length = ROUND_UP(s->bat_entries * sizeof(VHDXBatEntry), MiB); 1704 rt_bat->file_offset = ROUND_UP(VHDX_HEADER_SECTION_END + log_size, MiB); 1705 s->bat_offset = rt_bat->file_offset; 1706 1707 rt_metadata->guid = metadata_guid; 1708 rt_metadata->file_offset = ROUND_UP(rt_bat->file_offset + rt_bat->length, 1709 MiB); 1710 rt_metadata->length = 1 * MiB; /* min size, and more than enough */ 1711 *metadata_offset = rt_metadata->file_offset; 1712 1713 bat_file_offset = rt_bat->file_offset; 1714 bat_length = rt_bat->length; 1715 1716 vhdx_region_header_le_export(region_table); 1717 vhdx_region_entry_le_export(rt_bat); 1718 vhdx_region_entry_le_export(rt_metadata); 1719 1720 vhdx_update_checksum(buffer, VHDX_HEADER_BLOCK_SIZE, 1721 offsetof(VHDXRegionTableHeader, checksum)); 1722 1723 1724 /* The region table gives us the data we need to create the BAT, 1725 * so do that now */ 1726 ret = vhdx_create_bat(bs, s, image_size, type, use_zero_blocks, 1727 bat_file_offset, bat_length); 1728 if (ret < 0) { 1729 goto exit; 1730 } 1731 1732 /* Now write out the region headers to disk */ 1733 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE_OFFSET, buffer, 1734 VHDX_HEADER_BLOCK_SIZE); 1735 if (ret < 0) { 1736 goto exit; 1737 } 1738 1739 ret = bdrv_pwrite(bs, VHDX_REGION_TABLE2_OFFSET, buffer, 1740 VHDX_HEADER_BLOCK_SIZE); 1741 if (ret < 0) { 1742 goto exit; 1743 } 1744 1745 exit: 1746 g_free(s); 1747 g_free(buffer); 1748 return ret; 1749 } 1750 1751 /* We need to create the following elements: 1752 * 1753 * .-----------------------------------------------------------------. 1754 * | (A) | (B) | (C) | (D) | (E) | 1755 * | File ID | Header1 | Header 2 | Region Tbl 1 | Region Tbl 2 | 1756 * | | | | | | 1757 * .-----------------------------------------------------------------. 1758 * 0 64KB 128KB 192KB 256KB 320KB 1759 * 1760 * 1761 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1762 * | (F) | (G) | (H) | | 1763 * | Journal Log | BAT / Bitmap | Metadata | .... data ...... | 1764 * | | | | | 1765 * .---- ~ ----------- ~ ------------ ~ ---------------- ~ -----------. 1766 * 1MB 1767 */ 1768 static int vhdx_create(const char *filename, QemuOpts *opts, Error **errp) 1769 { 1770 int ret = 0; 1771 uint64_t image_size = (uint64_t) 2 * GiB; 1772 uint32_t log_size = 1 * MiB; 1773 uint32_t block_size = 0; 1774 uint64_t signature; 1775 uint64_t metadata_offset; 1776 bool use_zero_blocks = false; 1777 1778 gunichar2 *creator = NULL; 1779 glong creator_items; 1780 BlockDriverState *bs; 1781 char *type = NULL; 1782 VHDXImageType image_type; 1783 Error *local_err = NULL; 1784 1785 image_size = ROUND_UP(qemu_opt_get_size_del(opts, BLOCK_OPT_SIZE, 0), 1786 BDRV_SECTOR_SIZE); 1787 log_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_LOG_SIZE, 0); 1788 block_size = qemu_opt_get_size_del(opts, VHDX_BLOCK_OPT_BLOCK_SIZE, 0); 1789 type = qemu_opt_get_del(opts, BLOCK_OPT_SUBFMT); 1790 use_zero_blocks = qemu_opt_get_bool_del(opts, VHDX_BLOCK_OPT_ZERO, true); 1791 1792 if (image_size > VHDX_MAX_IMAGE_SIZE) { 1793 error_setg_errno(errp, EINVAL, "Image size too large; max of 64TB"); 1794 ret = -EINVAL; 1795 goto exit; 1796 } 1797 1798 if (type == NULL) { 1799 type = g_strdup("dynamic"); 1800 } 1801 1802 if (!strcmp(type, "dynamic")) { 1803 image_type = VHDX_TYPE_DYNAMIC; 1804 } else if (!strcmp(type, "fixed")) { 1805 image_type = VHDX_TYPE_FIXED; 1806 } else if (!strcmp(type, "differencing")) { 1807 error_setg_errno(errp, ENOTSUP, 1808 "Differencing files not yet supported"); 1809 ret = -ENOTSUP; 1810 goto exit; 1811 } else { 1812 ret = -EINVAL; 1813 goto exit; 1814 } 1815 1816 /* These are pretty arbitrary, and mainly designed to keep the BAT 1817 * size reasonable to load into RAM */ 1818 if (block_size == 0) { 1819 if (image_size > 32 * TiB) { 1820 block_size = 64 * MiB; 1821 } else if (image_size > (uint64_t) 100 * GiB) { 1822 block_size = 32 * MiB; 1823 } else if (image_size > 1 * GiB) { 1824 block_size = 16 * MiB; 1825 } else { 1826 block_size = 8 * MiB; 1827 } 1828 } 1829 1830 1831 /* make the log size close to what was specified, but must be 1832 * min 1MB, and multiple of 1MB */ 1833 log_size = ROUND_UP(log_size, MiB); 1834 1835 block_size = ROUND_UP(block_size, MiB); 1836 block_size = block_size > VHDX_BLOCK_SIZE_MAX ? VHDX_BLOCK_SIZE_MAX : 1837 block_size; 1838 1839 ret = bdrv_create_file(filename, opts, &local_err); 1840 if (ret < 0) { 1841 error_propagate(errp, local_err); 1842 goto exit; 1843 } 1844 1845 bs = NULL; 1846 ret = bdrv_open(&bs, filename, NULL, NULL, BDRV_O_RDWR | BDRV_O_PROTOCOL, 1847 &local_err); 1848 if (ret < 0) { 1849 error_propagate(errp, local_err); 1850 goto exit; 1851 } 1852 1853 /* Create (A) */ 1854 1855 /* The creator field is optional, but may be useful for 1856 * debugging / diagnostics */ 1857 creator = g_utf8_to_utf16("QEMU v" QEMU_VERSION, -1, NULL, 1858 &creator_items, NULL); 1859 signature = cpu_to_le64(VHDX_FILE_SIGNATURE); 1860 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET, &signature, sizeof(signature)); 1861 if (ret < 0) { 1862 goto delete_and_exit; 1863 } 1864 if (creator) { 1865 ret = bdrv_pwrite(bs, VHDX_FILE_ID_OFFSET + sizeof(signature), 1866 creator, creator_items * sizeof(gunichar2)); 1867 if (ret < 0) { 1868 goto delete_and_exit; 1869 } 1870 } 1871 1872 1873 /* Creates (B),(C) */ 1874 ret = vhdx_create_new_headers(bs, image_size, log_size); 1875 if (ret < 0) { 1876 goto delete_and_exit; 1877 } 1878 1879 /* Creates (D),(E),(G) explicitly. (F) created as by-product */ 1880 ret = vhdx_create_new_region_table(bs, image_size, block_size, 512, 1881 log_size, use_zero_blocks, image_type, 1882 &metadata_offset); 1883 if (ret < 0) { 1884 goto delete_and_exit; 1885 } 1886 1887 /* Creates (H) */ 1888 ret = vhdx_create_new_metadata(bs, image_size, block_size, 512, 1889 metadata_offset, image_type); 1890 if (ret < 0) { 1891 goto delete_and_exit; 1892 } 1893 1894 1895 delete_and_exit: 1896 bdrv_unref(bs); 1897 exit: 1898 g_free(type); 1899 g_free(creator); 1900 return ret; 1901 } 1902 1903 /* If opened r/w, the VHDX driver will automatically replay the log, 1904 * if one is present, inside the vhdx_open() call. 1905 * 1906 * If qemu-img check -r all is called, the image is automatically opened 1907 * r/w and any log has already been replayed, so there is nothing (currently) 1908 * for us to do here 1909 */ 1910 static int vhdx_check(BlockDriverState *bs, BdrvCheckResult *result, 1911 BdrvCheckMode fix) 1912 { 1913 BDRVVHDXState *s = bs->opaque; 1914 1915 if (s->log_replayed_on_open) { 1916 result->corruptions_fixed++; 1917 } 1918 return 0; 1919 } 1920 1921 static QemuOptsList vhdx_create_opts = { 1922 .name = "vhdx-create-opts", 1923 .head = QTAILQ_HEAD_INITIALIZER(vhdx_create_opts.head), 1924 .desc = { 1925 { 1926 .name = BLOCK_OPT_SIZE, 1927 .type = QEMU_OPT_SIZE, 1928 .help = "Virtual disk size; max of 64TB." 1929 }, 1930 { 1931 .name = VHDX_BLOCK_OPT_LOG_SIZE, 1932 .type = QEMU_OPT_SIZE, 1933 .def_value_str = stringify(DEFAULT_LOG_SIZE), 1934 .help = "Log size; min 1MB." 1935 }, 1936 { 1937 .name = VHDX_BLOCK_OPT_BLOCK_SIZE, 1938 .type = QEMU_OPT_SIZE, 1939 .def_value_str = stringify(0), 1940 .help = "Block Size; min 1MB, max 256MB. " \ 1941 "0 means auto-calculate based on image size." 1942 }, 1943 { 1944 .name = BLOCK_OPT_SUBFMT, 1945 .type = QEMU_OPT_STRING, 1946 .help = "VHDX format type, can be either 'dynamic' or 'fixed'. "\ 1947 "Default is 'dynamic'." 1948 }, 1949 { 1950 .name = VHDX_BLOCK_OPT_ZERO, 1951 .type = QEMU_OPT_BOOL, 1952 .help = "Force use of payload blocks of type 'ZERO'. "\ 1953 "Non-standard, but default. Do not set to 'off' when "\ 1954 "using 'qemu-img convert' with subformat=dynamic." 1955 }, 1956 { NULL } 1957 } 1958 }; 1959 1960 static BlockDriver bdrv_vhdx = { 1961 .format_name = "vhdx", 1962 .instance_size = sizeof(BDRVVHDXState), 1963 .bdrv_probe = vhdx_probe, 1964 .bdrv_open = vhdx_open, 1965 .bdrv_close = vhdx_close, 1966 .bdrv_reopen_prepare = vhdx_reopen_prepare, 1967 .bdrv_co_readv = vhdx_co_readv, 1968 .bdrv_co_writev = vhdx_co_writev, 1969 .bdrv_create = vhdx_create, 1970 .bdrv_get_info = vhdx_get_info, 1971 .bdrv_check = vhdx_check, 1972 .bdrv_has_zero_init = bdrv_has_zero_init_1, 1973 1974 .create_opts = &vhdx_create_opts, 1975 }; 1976 1977 static void bdrv_vhdx_init(void) 1978 { 1979 bdrv_register(&bdrv_vhdx); 1980 } 1981 1982 block_init(bdrv_vhdx_init); 1983